With advances in computing, such systems are employed in many aspects of communications, industrial control, and industry, in general. As manufacturing becomes more complex and specialized, computing systems and the data and software programs utilized to monitor and control these processes are essential. Downtime related to hardware and/or software failure becomes crucial in terms of cost, lost productivity, and output.
Manufacturing control and monitoring systems consist of and produce enormous amounts of data. This includes configuration data such as controller code, and alarm, HMI (human-machine interface) data, recipe and report definitions, to name just a few. Additionally, while running, control systems produce both real-time and historical data about the status of a given process including alarms, process values, and audit/error logs. For example, process control workstation displays can show the current state of process variables to an operator. Additionally, historical trend objects can display historical data from a persistent store such as a database or log file. For example, trend object users can “pan” backwards in time in a line graph plotting some process variable against time to instances of the process variable that were captured (and stored) at some point in history. (e.g., “last week”).
In typical distributed HMI systems the data is stored in a predefined location(s). HMI displays themselves—typically in the form of process overviews or machine detail displays—can show real-time (or last known) values to an operator. Multiple screens are created so that the operator can switch between them to view aspects of the system under control. Thus, these monitor and control screens that link to inputs and outputs for monitor and control of processes are important. Additionally, the data provided by such screens needs to be stored for later retrieval.
Typically, users are responsible for backing up and deploying the data files. Each client must have a network path to the data, and the server serving the data must be available and functioning. If the server is on a low-bandwidth path to a client or a set of clients, performance will suffer. Moreover, when the server is the central storage location, multiple remote system failures can burden the server during file and/or software retrieval, especially for large production control files and software. Thus, alternative mechanism for the safeguard and retrieval of such data is imperative for continued operation of such key systems.